%I #49 Jan 06 2015 22:59:09
%S 0,0,0,2,10,30,86,180,344,624,1056,1626,2522,3646,5118,7164,9784,
%T 12868,16848,21438,27202,34298,42550,51800,63184,76256,91032,108086,
%U 127850,149442,174902,202552,233608,268512,306664,349394,398226,450510,507038,569204
%N Number of sets of 4 distinct collinear points in an n X n permutation array in which leftmost pair has same spacing as rightmost pair.
%C Configuration of points forms a degenerate parallelogram.
%H Chris Swanson, Randy Ho, Bill Correll, Jr, <a href="/A234471/b234471.txt">Table of n, a(n) for n = 1..1000</a>
%Y Cf. A243643.
%K nonn
%O 1,4
%A _Christopher N. Swanson_, Randy Ho, and _Bill Correll, Jr._, Jun 08 2014